The present invention relates to an optical fiber and an optical transmission line using the optical fiber, particularly to an optical transmission medium suitable for the wavelength division multiplexing (WDM) transmission.
With the development of the information society, the volume of communication information tends to increase dramatically. According with such increasing information, the wavelength division multiplexing transmission has been widely received in communication fields. The wavelength division multiplexing transmission is a system where light having a plurality of wavelengths is transmitted through one optical fiber.
Currently, as optical amplifiers applied to relay points for the wavelength division multiplexing transmission, an optical amplifier using an erbium doped optical fiber (EDFA) has been developed. This optical amplifier amplifies signals as they are in the state of optical signals without converting the optical signals to electric signals. It is eliminated that the optical signals are converted to the electric signals at every wavelength in the relay points, which is accelerating the development of the wavelength division multiplexing transmission.
The invention is to provide an optical fiber suitable for the wavelength division multiplexing transmission and an optical transmission line using the optical fiber. The optical fiber in the invention comprising:
both dispersion and a dispersion slope in a waveband of 1570 to 1615 nm being negative values;
a bending loss at a diameter 20 mm in the waveband being 3 dB/m or under;
a transmission loss in the waveband being 0.3 to 0.8 dB/km, inclusive;
a value of polarization mode dispersion in the waveband being 0.5 psxc2x7kmxe2x88x921/2 or under;
a value that an absolute vale of a dispersion value is divided by the transmission loss in the waveband being 170 or above; and
a value that the dispersion value is divided by the dispersion slope in the waveband being 270 to 450, inclusive.